Can you farm out parts of renders to other iray machines?

I recently built a new computer running a 2080TI and was excited to start using it, but I've been having woes with some of my scenes with the beta client. In the process of building a new machine, my old build is just sitting there. It only runs a 970, so I normally just render my scenes on my laptop with a 1070. I was wondering if it's possible to farm out just parts of the render to different machines to speed up the process entirely? If so, do the cards all need to be able to fit the entire scene in it's VRAM? I suspect so, but I wanted to verify. Following that (still assuming it's possible), I imagine I'd need to let them finish completely in order for both outputs to match up, right?

Theoretically I have 3 machines available to run iray, can they all chip in to one render?

You can do spot renders and break the scenes into 2 rectangles or depending on the scene you may be able to turn off opposite elements and do 2 full renders with much less showing. Also works well for shooting through a door or window or having and outside building background render seperately from a foreground vehicle or model.